1. REPRODUCTION
CHAPTER 39

2. Sexual Development First six weeks Week 7 Birth Puberty
Male and female embryos are the same
Week 7
Ovaries and testes start to develop and produce hormones
Ovaries-estrogen
Testes-testosterone
Birth
Gonads produce small amounts of hormones
Puberty
Produce active reproductive cells

3. Puberty Rapid growth and sexual maturation
Reproductive system becomes fully functional
Usually between 9-15
Earlier in females
Triggered by hormones
FSH – follicle stimulating hormone
LH – luteinizing hormone

4. Male Reproductive System
FSH and LH stimulate testes to produce testosterone
FSH and testosterone stimulate production of sperm
Main function
Produce and deliver sperm
Scrotum
External sac holding testes
1-3 degrees lower than body temperature
Seminiferous tubules
Tiny tubules within testes where sperm are produced

5. Male reproductive system

6. Sperm Development Meiosis in testes to form haploid cell
Sperm is moved from seminiferous tubules into epididymis
Mature and stored here
Vas deferens
Extends up from scrotum until it merges with urethra

7. Sperm Development Urethra
Leads outside body through penis
Glands lining MRT contain nutrients for sperm and protect from acidic FRT
Seminal fluids and sperm are known as semen
million sperm in
1 ml of semen
Or 2.5 million per drop

8. Female Reproductive Tract
Ovaries – primary reproductive organ
Main Function
Produce ova (plural for eggs), prepare for and nourish embryo
Ovaries
Produce 1 egg per month (ovum)

9. Egg Development Follicles Surround a single egg
Help egg mature for release
Only about 400 eggs will be released in a lifetime
Every 28 days
Stimulated by the hormone FSH
Meiosis – 1 egg and 3 polar bodies

10. Egg Release Ovulation Fallopian tubes Uterus Release of egg
Fluid filled tube that carries egg using cilia to uterus
Opens over ovary
Fertilization occurs here
Uterus
Lining prepares for fertilized egg

11. Female Reproductive Tract
Cervix
Outer end of uterus
Opens to vagina
Vagina
Canal that leads to outside of the body

12. Menstrual Cycle “mensis” latin meaning month
Interaction of endocrine system and reproductive system
Starts at puberty
Ends at menopause
Around age 50
Egg develops and is released
Uterus prepares for fertilized egg
If egg is not fertilized, uterus lining is discharged

13. Phases of Menstrual Cycle
follicular, ovulation, luteal and menstruation
Follicular Phase
FSH and LH trigged by low estrogen cause follicle to develop
As follicle develops, estrogen rises, uterus lining thickens
10 days

14. Phase 2
Ovulation
Mature egg is released into one of the fallopian tubes
Shortest cycle
3-4 days

15. Phase 3 Luteal Phase Begins after egg is released
Corpus luteum forms where egg ruptured
Releases estrogen and progesterone
Best chance for fertilization is 2 days into luteal phase
10-14 days after completion of last menstrual cycle
If implantation in uterus occurs, embryo will release hormones that keep corpus luteum functioning for several weeks

16. Phase 4 Menstruation No fertilization? Corpus luteum will disintegrate
Less estrogen and progesterone
Causes lining of uterus to shed
Discharged through vagina
3-7 days
After menstruation ends, low levels of estrogen trigger FSH and LH to cause follicle to mature
Cycle starts over.

18. Sexually Transmitted Diseases
Diseases spread from one person to another during sexual contact or STD’s
Chlamydia
3 million cases per year
Caused by bacteria
Females show highest incidence
Can damage woman’s reproductive tract and cause infertility
Can pass from mother to newborn via childbirth
Can be asymptomatic or mild symptoms

19. STD’s Syphilis Gonorrhea Herpes, Hepatitis B, genital warts, AIDS
Caused by bacteria
Can be fatal
“great imitator”
Gonorrhea
Spread during intercourse
Herpes, Hepatitis B, genital warts, AIDS
All caused by virus
Cannot be treated with antibiotics
Prevention
Best
Abstain from sexual contact
Sex in a monogamous relationship
Next safest
Use latex condom

20. Fertilization and Development
CHAPTER 39.4